This is a revised application for an Independent Scientist Award. The candidate, Mark G. Myers, Ph.D., Associate Professor of Psychiatry at the University of California, San Diego, proposes to pursue a program of research focused on the process of cigarette smoking cessation among adolescents and cross-cultural variations in risk and protective factors for tobacco use initiation and progression among college students. The research plan includes three projects for which the candidate is Principal Investigator, two of which have been funded and are ongoing; the other ended recently and data compilation and analyses are underway. The candidate's career goals are: (1) to advance his progress in becoming a leader in the scientific study of the course of youth tobacco use; (2) to increase his expertise in statistical modeling techniques, cross-cultural research methodology, and qualitative research methods; and (3) to continue to mentor junior scientists. The candidate has made a strong commitment to tobacco-related research. Activities for his continued career development include: (1) consultation with leading research scientists; (2) coursework in the analysis of longitudinal data, cross-cultural research methods, qualitative methods, and the responsible conduct of research; and (3) participation in department seminars and scientific meetings. Funding of Dr. Myers Independent Scientist Award will provide him the opportunity to substantially increase the time devoted to research activities, thus enhancing his development as a scientist and as a mentor.